Sliding jaw screw cap jar wrench



Feb. 16, 1954 E. B. DAVIS SLIDING JAW SCREW CAP JAR WRENCH 2 Sheets-Sheet l Filed June 29, 1951 Feb. 16, 1954 E B DAVls 2,669,141

SLIDING JAw SCREW CAP JAR WRENCH Filed June 29, 1951 2 Sheets-Sheet 2 'lllll Patented Feb. 16, 1954 UNITED- STATES TENT OFFICE SLIDINGJAW SCREW CAB'JAR WRENCH EdgarBL Davis, Tangerine, Fla..Y

Application June 29, 1951, SerialNo-f2`34g214 13 Claims. (01; S1- 3542) I1 This: application a, continuation in part of myf cof-pending application' Serial No. 1'5318'75` lediMarch; 31, 1950, now abandoned..

inventionrelatestto fa' screw cap jar; openen. and: more particularlyv t'o a screw' capv jar opener of thekind toV bevmore'particularly described.'hereinafterihavinglmeansi'for limiting. the clamping' action'A of: the: jar.- opener" on the; screw cap, irre:l manner vte prevent thezbreaking ofthe jarsuponf arr application of anexcess force. being applied towtl'e screw'cap.

It thasfor'one .objectftov provide avv screw cap l j ar opener havingrayieldable; resilient, pawl member for: positioning: the: movable' clamping jaw memlierf-innclampingV engagement 'with' a screw-'cap to beisremeveda from ai. glass.` j ar; the yieldable.l pawl membenbeingbendable. upon applicationl off' an undue'forcef exerted on` thexhandles offthe screw jarf'opener toi preventtha accidental breakingl or crack-litigi` of' the glass jaw" on which. the capf is engaged;

Anothen: object" off the.' invention vis to` provide an: automatic;l self-adjusting;` built inv flexibility inithe screw rcap .j ar.; opener inl orden to provide:` a jar op enerwhiclfrissafe fiore; userfwhen :removing caps fromvglassjars andnov severe crushing.` effect be: applied: to" the -caprwhen 4removing-or appiyingz' plastic.y and. thin metal caps;A

Another object of: theinvention:iszto'prov-ide a:.screw'cap:jar opener havingaaf minimuminumber-r of: efectivei. partse operatively connected togetliertcuprovide-a screw` cap jar opener of this lndz' resulting. int lower: production costs; for: the devicezwhich in" turn; leads-:to the; lower' price"I of the: device. forthei consumer.

Anothen obj ectofl myf invention is Lto providefin connection with a wrench` having;y opposed handles and' mea-nsf actuated by*Y the opposed handlesvtodrawsfopposed jaws.- togetherrwherein if? excessive" pressure applied: to the handles; the.7 drawing: togetherr of ther' jawstherebyf is sharply and suddenly limited to prevent the ap*- plicat'ionf: of: excess,I 1 pressure on the object-,being handled;

While?y I: have: illustrated; Inyvinvention` as.V ap plieziif. to: a jar: opener; it; will; be'4 obvious 'it'. may equally Well-'befapplied-to any yother device-where twjaws' are brought v.together to grip. anfobject.

invention: is:r illustrated mores or lesse, dia. grammatically in the accompanying drawings;

wherein; C

liiglille:I lgiszastop plan' view/of L a: screw can;l jar opener;

Eigurefis azside elevation;y f

v Eigureisis ai fragmentary, horizontal,- longitui, dinal section taken on the line 3-3 of Figure 2;

Figure 4 is a transverse section taken onthe lined- 4 offligurer;`

Figure. 6 isl a fragmentary,` detailed side elevan tion; partly broken away, showing the engage;- ment of the pawl' with the serrated or toothed edge of thevbarg;

Figure '7v is a bottom plany view oi. ai modied form of the device;

Figure 8 is a sectionralonggthesline 8*-8of`Figurec;

Figure 9 isfapartial top planfview of apart'of the device shown in liligureil;`

Figure 10` is' ai detail view similary to Figure- 7 showingy the'. partsiinf ai different position Figure 1 l is a: piani view in' part `sectionsimilar to Figure'lO showingstheparts inra' further stage of compression; l

Figure 12 is a section aflongftheliney I 2?-I2f of Figure 8;

Figure 13. is? a' section along, theV line I3- I 3v of Figure 8 ;i

Figure. 1A is aiviewsimilarrto FigurelO: showing finale gripping., position; and' Figure 15: issalseparate-plan view ofthe wrench body.

lliikeI parts are indicated. by like characters throughout the specification and drawings;

Referring: to the? drawings; ther numeral.y IIJ designates generally 'a safetyscrew capl jar open@ er constructed? according to'v an embodiment of my inventiom. The" screw cap jar.' openerv I0 is adapted to' berclampingly engaged with a' metal screw cap: I l engagedxontheupper threaded end of a glass;` bottle.` or'jar, as: the .cap of'. glass*v can ning jars generally' and popularly in: use: In order to' prevent. the crushing" of the` screw cap- I'I to thefpoint off snapping orjcra'cking` the 'glass' jar; the screw-'cap jar'opener' Ifis'provided with af yieidablef means engaging the movabler clamp-- ing jaw' for'releasingthe movable clamping`l jaw from its'A engagement with .the screw' cap" I I`v upon the application of apredet'ermined; unduerforce;

The screw'capijar opener Itif;isfforn'ledwth` a longitudinally extending, yliat barrmember |12N have ing a xed jaw member i4 xed to, or" formed integrally with; oneendtth'ereof'.'v The'v opposite side edges-i-.and Iifofzthebar IZzmaybe serrated' or!v formed'jwithclosely. spaced apart, small; ratchet. teeth: Il*v with' which apawl. member, to" be. more specifically described! hereinafter is adapted Jto be. engaged..

Awrenchbody I8 is. slidably'l engaged onthe bar I2" for sliding movement along. the length.

thereof. The Wrench body I8 is formed ofa at sheet of metal bent at its forward end in a manner to provide a sliding channel member IS on the upper side of the forward edge thereof for overlying the upper edge i5 of the elongated bar i2. A similar, confronting channel member Eil is formed on the opposite side edge of the front portion of the wrench body I8 and is adapted to slidably engage over the lower edge I6 of the longitudinally extending bar i2 for slidably supporting the wrench body i3 thereon. The channel members i9 and 2li extend only a short distance rearwardly from the extreme forward edge of the wrench body it, and the rear portion of the wrench body i8 is ilattened out to form an upwardly extending arm 2i and a depending arm 22, as clearly noted in Figure 4 of the drawings. The upwardly extending arm 2| will form a pivot member for supporting an upper pivot pin 24 and the depending arm 22 will form a journal below the lower edge of the bar I2 for the lower pivot pin 25.

A movable or slidable clamping jaw member 26 is slidably supported on the bar I2 and is slidably engaged between the channel members I9 and 2i) and the bar i2 for slidably supporting the movable jaw member 26 within the wrench body I8 in the manner clearly noted in Figure 5 of the drawings. rThe movable jaw member 2S is slidably carried by the wrench body I8 for extension and retraction therefrom, in a manner to be more particularly described hereinafter. At the rear end of the slidable jaw member 2t there is formed a laterally extending abutment member 21 which is adapted to be engaged by the handle of the jaw opener for sliding the movable jaw member 2S forwardly from the Wrench body I8 for clamping engagement with a screw cap, as the screw cap il, which screw cap will be clampingly engaged between the iixed jaw member M and the movable jaw member 2li.

An upper handle 28 is pivotally mounted at one end on the upper pivot pin 24, and a lower, confronting handle 29 is pivotally mounted on the lower hinge pin 25, as clearly noted in Figures 1 and 3 of the drawings. Each of the handles 28 and 2li is formed of a sheet of metal bent upon itself to dene a pair of longitudinally extending, channel-shaped handle members open on the confronting sides thereof.

A depending lever arm 30 is formed on the upper handle member 28 extending downwardly a considerable distance below the upper pivot pin 2liand an upwardly extending lever arm 3i is formed integrally with the lower handle member 29 extending upwardly therefrom to a point slightly spaced from the longitudinal median of the bar i2. The upper lever arm 3o is formed with a cut out portion 32 on the lower edge thereof and the upwardly extending lever arm 3l is formed with an upwardly opening cut out portion 34 on the upper end thereof defining therebetween Aa recess within `which the outwardly extending abutment member 2l' carried by the movable jaw member 2li is adapted to be engaged for connection to the pivotally mounted handles 28 and 29, clearly noted in Figures 3 and 4 of the drawings.

An upper, resilient pawl member 35 is carried by the upper handle member 28, and a lower, resilient and yieldable pawl member 35 is carried by the lower handle member 23 for tensioning the movable clamping jaw 26 into clamping engagement with a screw cap l I upon pivoting the handles 28 and 2S together about the respective pivots 24 and 25.

The upper, resilient and yieldable pawl member 35 is formed of a short length oi wire Iwhich is coiled about the upper pivot pin 24 and has one end thereof engaged in the handle 28 and extending a short distance along the length thereof. The other end 39 of the pawl member 35 extends downwardly and rearwardly from the pivot pin 24 to be engaged between the teeth II on the upper edge I5 of the bar l2 upon swinging of the upper handle 28 downwardly about the pivot pin 24 into a position substantially parallel to the bar I2. rllhe lower, yieldable pawl member 36 is formed in substantially the same manner as the upper, yieldable pawl member 35 of a short length of fiat wire at least partially coiled about the lower pivot pin and having one end extending longitudinally a short distance along the length of the lower handle 29. The other end of the lower pawl member is provided with a point 40 for engagement between the teeth Il on the lower edge It of the bar I2. Being of la resilient and springy nature, the pawl members 35 and 36 also act as resilient spring means for biasing the handles 28 and 29 apart into a divergent, normal relation about the pivot `pins 24 and 25 in the open position of the screw cap jar opener.

As the lever members and 3| of the handles 28 and 29, respectively, engage the outwardly extending abutment member 21 of the movable jaw member 26 upon pivoting of the handles 28 and 29 together about their respective pivots, the respective pawls and 36 will initially engage the serrated or toothed edges of the central bar I2 for holding the handles and movable jaw member against sliding in one direction thereon. Further pivotal movement of the handles together will effect the forward swinging movement of the levers 30 and 3I, whereupon the movable jaw member 26 will be slidably moved forwardly from its engagement in the wrench body I8 to a clamping position for engaging a screw cap II between the xed clamping member I4 and the movable jaw member 26. Upon the application of an undue force on the handles 28 and 29 for pressing the movable jaw member 26 forwardly, the rearward inclination of the resilient pawl members 35 and 36 will provide for the release of the pawl from the respective edges of the bar I2 so that no undue force may be applied to the handles 28 and 29 for pressing the movable jaw member 26 into engagement with a screw cap II with a force suflicient to crack the glass jar on which the cap is mounted.

For removing the screw cap jaw opener from its engagement with the screw cap II, the handles 2B and 29 may be moved divergently about their respective pivot pins for disengaging the respective pawls 35 and 36 and providing for the free sliding movement of the wrench body I8 and movable jaw member 25 rearwardly along the length of the bar I2 out of engagement with the cap II.

In order to hold the handles 28 and 29, together with the wrench body I 8 and the movable jaw member 26, on the bar I2, an abutment member or detent 4I is formed on the end of the bar I2 remote from the xed clamping jaw I4 for engagement with the wrench body IB in the most rearward position of the wrench body and the handles 2&1 and 29. l

While the terms upper and lower have been used in the application to define the handle members 28 and 29, it will be understood that. such a descriptionV is used merely in reference to the drawings to clearly denote these mempivot" arm4 581;

v bers; butliti will be` understood thatizin the.L gen-f eltal useio'a'- deviceof.: this'l kind; the z handles=c2$ 'andi 25- Will i be 1 disnosc-zd5 in'. a horizontal, side'f by sidef` relation:

Infthefembodimentoi Eigures to'4 1:4, S'iisra wrench: bodylr It enclofses` a Y fixed jaw.` plate' 511, laterally?` projecting from it-QisanJnner jaw.' 52.

'The wrench'. body also: enclosesz an: adjustable jaw: vbar 53: fromzI which: projects; laterally.' a': jaw Sdinzoppositionto the'ja-wfz. The nxed jawfplate 5.1:? and theA adjustable'- jawfv befrv 532 are held'? in slitlable' relationship' with one4 another 'andi with the-wrenclfi1` body 5D by,theii'angesvV fwhich are integral With'the'wreneh' body.; the platei 4andilianl being slide-ble one with'4 respect to theother butconstrain'ed by: the'vwrench body to'para'l1elmovement. 5.1, 5% arepivotlarmsrex 'tendinglaterallyffrom' the wrenchfbody; 5U: Han `dies SSfandf 60! enc-lose tlrie'pivot'l arms 5T; 58*- and are pivotedV on' saidff arms'r Extending: inwardly fromthe' handles 59C and 611 are clamping: levers dit'. 62E eachlever5 terminating in' a slot 63, B4, the-slots1being narrow' atv-the ends of the lever arms1 but;v ofgreater size further in for clear'- ance. 65 is a driving lug integral" Withfthe-jaw plate 5W soi that'A when: they handles`- 59 and 6i! aredrawn'f together; the ylevers 6l and 6.2 move to the left inf Figure 'r 7 and in view-'- of their interlcking'with the-'vlug 65;- tliey cause-'a forward movement ofthe-jaw plate 5i and' jaw 52'with respectE to' the=wrench body;

SSis' a spr-ing'assooiated with' the handle 59 and'fthe; pivot` arm'- 575, biasing the 'handle' 59` to open l positionl andv because the handle 59 i is con'- neot'edl-to' thehandl'e 6B" through the lug 65'4v and the leverarmtl and 62; ther-spring E6 also biases thelhandle Blite open position;

Theljaw'bar'5'31is1serrated`as atA 6l' along one edge. In opposition to this serrated'- edge is' a dogflisv having a plurality of" teethadaptedy to mesh Witlithe'serrationlrl; the -teeth' on dog and barbeingofthesame' contour; The dog 68 is pivoted'l concentric with'v the' handlev 60'* on the 69@ is a spring anchored on' the handle 60 at one end and at the other endL permanently attached' to the'dog so'that when thej parts' are in the' position' shown' inl Figure 7 with the'handlesv' in open-position the dog' S8l is out; of contact with the serrated* edge' or' rack orrtlie'fjaw bar-53. Under-these circumstances, when'the parts are'ingthe'eposition'shown` in Fig'- ure 7;' the'user is'free tomove`theslidingbar-53 back' and'- forth` within the wrench body to' adljust manuallythefdistance between the wrench jaws' 52', 54. Theymay' be broughtA sov closely together-"that'they touch'or'thevA may be' brought so' far' apart' that the stop memberl on the barf 53T- engages the` jaw f plateA 5l toA limit' further movement, all this Without' any movement` of the handles Whatever.'

When-*the wrench is-'to--be-use the two jaws 52 and 54'@ are4 brought against opposed` sides" of the j'artop for other object to be openedor'turned by vsliding 53'- in'- 5il1'which`- can` easily' be' done be'- Acause-the'- dog'is'out-'of contact with the' sliding bar. together, a very slight' rotation brings' the. dosr Then the' user. squeezesv the' two'r handles intoY engagement with theA serrated: edge of' the sliding' bar.' Further rotation` off thev handles tendsstovmove-'the ixedt jaw plate outwardly.' in

.untih theI levarsi 6i; Se engage;l thea flangesfrm on .6 "theawrenchihodyratwhiclntimefnofiurthenmtary movementlzoxthefyhandle:abouttheinpivoti,inzthe closing direction is'poss-ibler.

In Niewof the fact .that thezwrenchziss intended bel., used? tot. unscrewr. delicate` or thin'. screw caps fon; glass-bottles andjars; .it will be: obvious that excess pressure brought bytheuser-z onilthe handles'zmightzcrush'iieszcaps andievencrushthe jarstso theainterlockf4 .between the clog;v En@ and 1 the teeth. Giliy is not' ax. positive one; The teeth are slanted teeth. They areA held. together' by: the pressure: of." the spring. 69:.' If theforceldrawing the jawsiit and154i. together becomes too'strong, the;userf'havingspressed too hard on the. handles, the dogs' Willsl'ipfone' notchgthe'spring 69 being compressed.'y sufficiently.v to. allow the dog teeth toy slide zoutand. engage the tooth'. barl one. tooth further-whack'. The Y. arrangement .andi relation of the partszis such'. that.' underf ordinary" circums tan'cesxonf-rr tooth movement: is: all` thati` is. perf-'- mitted; Further` movement, is= prevented; be,- cause of the-..1imiting;contact off the ,levers' l', 52 tvithztheslugsfr.

The spring: 6B: works ,-both; ways: Itiholds the degr @8f againstA the teeth'i 6l' when the handles 59. andifare; brought together but it; positively drawsvthe dogliii -away fromthe teethy $1 when the spring; 6Ei is-.allowed'to ,open the handles, thus making it; easy.' for. 'the' user to adjust the' J'aWs bach; and;I forth tuitxthef size of jarl or other Qb'jectzzbeing treated? wthoutzinterference by the teetl'ifofidogahdiadjlistingbar.

Itz essential'y that the relationship'- between the two: jaws-and` the handlesbe such that no mattei: how`v hard: the; operatorfsqueezes: on the handles. hefl will.4 not:` crush. and break' the bottle. ril'ieestops'tfliniit: the movement of the levers 6| and 62 and so limit the'maximum movement of.'"the.jaw'52xl toward the'jaw 54". This limitationzisipresentWhether'the: dogl 681 is able to 1j ump one'vtooth; en the'.:member`- 53fcr not. andi' the pro'- vision: which' permitsajump-ingfof `a single tooth merely, is an; added` safeguard'. against crushing theglass;r jar: The essential', thingV is that no matterrhow; 'they work; .meansare provided'which eifeetivelyn preventE suchk movementA of jaw. 52 toivardjawf aswouldbe sufficient to crush the gainagains't. the: jal': and break the' jar. Slight movement isfessential to grip the2cap- Excessive movement wouldfbreak the jar-andsuch-excessive movement is@ eiectually`v avoided inmyinvention.

I claim:

1'; A- jarfopener comprising anV elongatedv` bar having ajaw'on'one end, a-body-member slid'able on saidbar', a jaw member slidable' in 'saidbody member; a pair-of^ opposed 'handles' pivotedv on said'body' member; a lever'arm on 'each' of' said handles engaging said'l jaw member' for" sliding said? jaw/member in the direction of the'jaw on the bar; andi aI pawl 'membercarried" by each handle en'gageable' with' said bar' for vreleasaloly positioningf'said j'aw'memberon said` bar upon pivoting saidt handles togetherl for clampingly 'engaging'a jar-cap between' the jaw and' said jaw member, engagea-ble; means on said; elongated' bar for receptionof* said' pawl.' so. as lto provide firm' contact therebetween', said" pawl members :beingv releasa'bleV from said' bar upon separating' said handles for removing the jar ftomathecapnengag ed thereby.'-

2; mjarffopenel: for; a:w jar' havingl a screw cap comprising@ anzelongated bar having-a jaw mem berfxedthereon; a body-memberslidablefonvsaid banaaaseecnct jaw: member. slidahie'l on saidlbody member, a handle pivoted on said body member and engaging said slidable jaw member, and a resilient pawl member carried by said handle for engagement with said bar for sliding said movable jaw member in the direction of said iixed jaw member upon rocking said handle on said body member.

3. A jar opener for a jar having a screw cap comprising an elongated bar having a jaw member fixed thereon, a body member slidable on said bar, a second jaw member slidable on said body member, a pair of handles pivoted on said body member and engaging said slidable jaw member, and a resilient pawl member carried by each of said handles for engagement with said bar for sliding said movable jaw member in the direction of said fixed jaw member upon rocking of said handles together on said body member.

4, A wrench including a wrench body, a pair of handles pivotally mounted thereon for movement toward and from one another, means biasing said handles to the `open position, a short, carrying slide member slidably mounted in the body having a jaw projecting therefrom at right angles te the plane of the handles, one of the handles having a lever rotatable therewith, a lug projecting from the short slide member engaging the lever whereby movement of the handles toward one another forces the jaw on the short slide member away from the body, a long adjustable jaw carrying member slidable in the body having a jaw in opposition to the first-mentioned jaw, the edge of the adjustable member being serrated, a dog pivoted on the wrench body, and a connection between the dog and one o the handles whereby movement oi the handles toward one another causes the dog to engage the serrations.

5. A wrench including a wrench body, two parallel jaw carrying members slidable therein, a jaw on each in opposition to the other, handles pivoted on the wrench body for movement toward and from one another, means biasing the handles to the open position, one jaw member being adjustable in the body, means between the said one j aw member and at least one handle for locking the said one jaw member against movement in one direction when the handles are actuated, a driving -connection between the other jaw member and one of the handles whereby movement or" the handle causes the jaws to approach one another.

6. A wrench including a wrench body, two parallel jaw carrying members slidable therein, a jaw on each in opposition to the other, handles pivoted on the wrench body for movement toward and from one another, means .biasing the handles to the open position, one jaw member being adjustable in the body, a driving connection between the other jaw member and one of the handles whereby movement of the handle causes the jaws to approach one another, means interposed between said one jaw member and one of the handles to lock such member against movement with respect to the body as the handles approach one another.

7. A wrench including a wrench body, two parallel jaw carrying members slidable therein, a jaw on e-ach in opposition to the other, handles pivoted on the wrench body for movement toward and from one another, means biasing the handles to the open position, one jaw member being adjustable in the body, means between the said one jaw member and at least one handle for locking lthe said one jaw member against movement in one direction when the handles are actuated, a driving connection between the other jaw member and one of the handles whereby movement of the handle causes the jaws to approach one another, the driving connection including a lever on one of the handles and interlocking means interposed between it and the jaw.

8. A wrench including a wrench body, two parallel jaw carrying members slidable therein, a jaw on each in opposition to the other, handles pivoted on the wrench body for movement toward and from one another, means biasing the handles to the open position, one jaw member being adjustable in the body, means between the said one jaw member and at least one handle for locking the said one jaw member against movement in one direction when the handles are actuated, a driving connection between the other jaw member and one of the handles whereby movement of the handle causes the jaws to approach one another, the driving connection including a slotted lever on one of the handles, a lug integral with the jaw member extending perpendicular from one side thereof and interlocking with the slot in the lever.

9. A wrench including a wrench body, two parallel jaw carrying members slidable therein, a jaw on each in opposition to the other, handles pivoted on the wrench body for movement toward and from one another, means biasing the handles to the open position, one jaw member being adjustable in the body, a driving connection between the other jaw member and one of the handles whereby movement of the handle causes the jaws to approach one another, means interposed between said one jaw member and one of the handles to lock such member against movement with respect to the body as the handles approach one another, the jaw member locking means including a plurality of serrations on the jaw member, a dog pivoted on the wrench body and a driving connection between one of the handles and the dog whereby closing movement of the handles causes engagement of dog and serrations.

10. A wrench including a wrench body, two parallel jaw carrying members slidable therein, a jaw on each in opposition to the other, handles pivoted on the wrench body for movement toward and from one another, means biasing the handles to the open position, one jaw member being adjustable in the body, a driving lconnection between the other jaw member and one of the handles whereby movement of the handle causes the jaws to approach one another, means interposed between said one jaw member and one of the handles to lock such member against movement with respect to the Ibody as the handles approach one another, the jaw member locking means including a plurality of serrations on the jaw member, a dog pivoted on the wrench body and a driving -connection between one of the handles and the dog whereby closing movement of the handles causes engagement of dog and seri-ations, the driving connection including a flexible element which can yield to permit limited movement of the dog along the serrated surf-aces.

11. A jar opener for a jar having -a screw cap comprising an elongated serrated bar having a jaw member fixed thereon, a wrench body slidable on said bar, a second jaw member slidable on said wrench body, a pair of handles pivoted on said wrench body and engaging said slidable jaw member, and a resilient pawl member carried by each of said handles for engagement with the serrated portion of said bar for sliding said movable jaw member in the direction of said xed jaw member upon 'rocking of said handles together on said wrench body, the resiliency of the pawl member being such as to release its hold on the bar to permit limited movement of the jaw members relative to each other upon excessive clamping pressure .of the jaw members against a screw cap to be removed.

12. A jar opener for a jar having a screw cap comprising anfelongated serrated bar having a jaw member fixed thereon, a Wrench body slidable on said bar, a second jaw member slidable on said wrench body, a pair of handles pivoted on said wrench body and engaging said slidable jaw member, and a yieldable resilient pawl member ycarried by each of said handles for engagement with the serrated portion of said bar for locking said slidable jaw member from movement in a direction away from said xed jaw member upon rocking of said handles together on said .wrench body, said pawl being yieldable upon application of a predetermined clamping force applied on said movable jaw member for clamping a jar cap between said jaw members.

13. A jar opener for a jar having a screw cap comprising an elongated serrated bar having a jaw member xed thereon, a wrench body slidable on said bar, a second jaw member slidable through said wrench body, a handle pivoted on said Wrench body and engaging said slidable jaw member, and a resilient pawl member carried by said handle for engagement with the serrated portion of said bar for locking said wrench body against movement with respect to the said fixed jaw member upon rocking said handle on said wrench body, the resiliency of the pawl member being such las to release its hold on the bar to permit limited movement relative to the bar upon the application of excessive clamping pressure.

EDGAR B, DAVIS.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,967,960 McNemar July 24, 1934 2,503,471 Chester Apr. 11, 1950 2,507,789 Jessup May 16, 1950 

